Module reference_frame 

Geodetic reference frame transformations

Transform coordinates between geodetic reference frames using time-dependent Helmert transformations. Supports both global frames (ITRF series) and regional frames (ETRF, NAD83, etc.) with runtime parameter loading.

Key Concepts

• Reference frames define coordinate systems for Earth positioning
• Crustal motion causes positions to change over time, requiring velocity tracking
• Transformations use 15-parameter Helmert models with time dependencies
• Path finding automatically chains transformations between frames

Core Types

• ReferenceFrame - Enumeration of supported coordinate systems
• TransformationRepository - Manages transformation parameters and pathfinding
• Coordinate - Position with reference frame, epoch, and optional velocity
• TimeDependentHelmertParams - 15-parameter transformation model

Basic Usage

use swiftnav::{
    coords::{Coordinate, ECEF},
    reference_frame::{TransformationRepository, ReferenceFrame},
    time::UtcTime
};

let repo = TransformationRepository::from_builtin();
let epoch = UtcTime::from_parts(2020, 3, 15, 0, 0, 0.).to_gps_hardcoded();

// Create coordinate with position and velocity
let itrf_coord = Coordinate::with_velocity(
    ReferenceFrame::ITRF2014,
    ECEF::new(-2703764.0, -4261273.0, 3887158.0),
    ECEF::new(-0.221, 0.254, 0.122),
    epoch
);

// Transform to different reference frame
let nad83_coord = repo.transform(&itrf_coord, &ReferenceFrame::NAD83_2011)?;

Custom Transformations

let mut repo = TransformationRepository::new();

let custom_transform = Transformation {
    from: ReferenceFrame::ITRF2020,
    to: ReferenceFrame::Other("LOCAL_FRAME".to_string()),
    params: TimeDependentHelmertParams::default(),
};

repo.add_transformation(custom_transform);

Structs

ReferenceFrameIter

An iterator over the variants of ReferenceFrame

TimeDependentHelmertParams

15-parameter Helmert transformation parameters

Transformation

A transformation from one reference frame to another.

TransformationNotFound

Error indicating that no transformation was found between two reference frames

TransformationRepository

A repository for managing reference frame transformations

Enums

ReferenceFrame

Geodetic reference frame identifiers